Warp knitting pile method involving orientation by modifying warp



A nl 17, 1962 R. s. M CAFFRAY, JR 3,029,621

WARP KNITTING PILE METHOD INVOLVING ORIENTATION BY MODIFYING WARP Filed Nov. 50, 1959 12 Sheets-Sheet l INVENTOR ATTORN EYS A ril 17, 1962 R. s. M CAFFRAY, JR 3,

WARP KNITTING PILE METHOD INVOLVING ORIENTATION BY MODIFYING WARP Filed Nov. 30, 1959 12 Sheets-Sheet 2 April 17, 1962 R. S. M CAFFRAY, JR WARP KNITTING PILE METHOD INVOLVING ORIENTATION BY MODIFYING WARP Filed Nov. 50, 1959 12 Sheets-Sheet 3 INVENTOR April 17, 1962 Filed Nov. 30, 1959 R. S. M CAFFRAY, JR

WARP KNITTING PILE METHOD INVOLVING ORIENTATION BY MODIFYING WARP 12 Sheets-Sheet 4 A ril 17, 1962 R. s. M CAFFRAY, JR 3,0

WARP KNITTING FILE METHOD INVOLVING ORIENTATION BY MODIFYING WARP Filed Nov. 30, 1959 l2 Sheets-Sheet 5 INVENTOR April 17, 1962 Filed Nov. 30, 1959 R. s. M cAFFRAY JR 3,029,621

WARP KNITTING PILE METHOD INVOLVING ORIENTATION BY MODIFYING WARP l2 Sheets-Sheet 6 INVENTOR fez, J? Mum 9 g!! April 17, 1962 Filed Nov. 50, 1959 R. S. M CAFFRAY JR WARP KNITTING PILE METHOD INVOLVING ORIENTATION BY MODIFYING WARP 12 Sheets-Sheet 7 April 17, 1962 Filed Nov. 30, 1959 R. S. M CAFFRAY, JR WARP KNITTING PILE METHOD INVOLVING ORIENTATION BY MODIFYING WARP 12 Sheets-Sheet 8 INVENTOR fi J /WW April 17, 1962 Filed Nov. 30, 1959 R. S. M CAFFRAY, JR WARP KNITTING FILE METHOD INVOLVING ORIENTATION BY MODIFYING WARP 12 Sheets-Sheet 9 INVENTOR April 17, 1962 s, MaccAFFRAY, JR 3,029,621

WARP KNITTING FILE METHOD INVOLVING ORIENTATION BY MODIFYING WARP l2 Sheets-Sheet 10 Filed Nov. 30, 1959 a I k &

INVENTOR April 17, 1962 R. s. Ma CAFFRAY, JR 3,029,621 WARP KNITTING FILE METHOD INVOLVING ORIENTATION BY MODIFYING WARP l2 Sheets-Sheet 11 Filed Nov. 30, 1959 INVENTOR Eel J. mac'afj zufcfn ATTORNEYS April 17, 1962 s, MaGCAFFRAY, JR 3,029,621

WARP KNITTING FILE METHOD INVOLVING ORIENTATION BY MODIFYING WARP Filed Nov. 30, 1959 12- Sheets-Sheet 12 INVENTOR Re; 5. Mafia/fray, :51 we A 5 ATTOR N EYS 3,02%,621 G FILE METHGD ENVGLVHN G ORENTATION BY MQDWYEJG WA Rex S. MacCafiray, Jr., Boiiing Springs, Pa., assignor to C. H. Masiand and Sons, Carllisie, Pin, a corporation of Pennsylvania Filed Nov. 39, 1959, Ser. No. 856,263 15 Claims. (1. 66-455) The present invention relates to methods of warp by means of two warp ends for each pile yarn end, at

least one of which warp ends is formed into knitted stitches, and the other of which warp ends may be formed into knitted stitches or laid into the knitted stitches.

A further purpose is to increase the tuft bind in warp knitted pile fabrics by use of two binding warps, at least one of which forms knitting stitches.

A further purpose is to reproduce a texture pattern in loop pile fabrics such as carpets or the like, especially level loop pile fabrics, by the use of a modifying warp end for each pile warp.

A further purpose is to produce a more glamorous and attractive pile fabric using a single guide bar for pile yarn, without the necessity of burying extra pile yarn or using extra laid-in pile yarn.

A further purpose is to avoid the alternate row effect, sometimes called the rowy effect, which is commonly associated with knitted pile fabrics.

A further purpose is to knit a pile fabric in which the legs of the pile projections are erected and held between stretches of two different warp yarn ends.

A further purpose is to first lock the forward or newly formed leg of each of the pile projections (loops) under the top stretches of knitting warp yarn stitches, and at the time of forming the pile projections, make this top stretch of knitting warp yarn pass around one side of the legs of the pile projection at the same time that an end of modifying warp yarn passes round the opposite side of the legs of the pile projection, the modifying warp yarn then. being laid-in and bound under the same top stretch of knitting warp yarn.

A further purpose is first to hold the forward or newly formed leg of each one of the newly formed pile projections by means of a modifying warp end which passes around and over the base of each leg of the pile projection and which then is laid into the knitting warp stitch, the forward leg of the newly pile loop crossing over the newly formed warp chain stitch and being in a position so that it will be locked under the top stretch of the next warp chain stitch but not under the top stretch of the chain stitch of the present course.

A further purpose is to provide pile projections of pile yarn with legs which are laid into stitches of warp knitting yarn, with a modifying warp yarn above the warp stitch binding point of the legs, the modifying warp yarn being laid into the same loops of warp knitting yarn, by shogging and moving opposite to the knitting yarn so that the modifying warp yarn ends will clamp the legs of the pile projections against the top stretch of the warp knitting yarn stitch, and will cause the legs of the pile projections to be erected into a vertical position or a position inclined from the vertical depending upon the tension in the modifying warp ends, at the same time orienting the pile projection in proportion to the tension applied to the modifying warp ends.

A further purpose is to produce a surface texture pattern in a piie fabric by selectively controlling the tension on the modifying warp ends for each individual end and for each stitch, the modifying warp ends pressing against the legs of the pile projections and moving in each stitch opposite to the knitting chain, and the modifying warp ends by tension clamping the legs of the pile projections between the top loops of the knitting stitches and the modifying warp ends. Thus under a high tension of the modifying warp ends one type of pile orientation will be obtained and under a lesser tension a dilferent type of pile orientation will be obtained, due to the looser clamping action exerted on the legs of the pile projections against the top stretches of the knitting chain.

A further purpose is to produce a warp knitted pile fabric with a backing of sinuously laid-in backing yarn, warpwise lines of warp chain stitches locking the weftwise backing yarn into a flat fabric, face or pile yarn with legs of the pile projections held in the stitches of the knitting chain, and modifying warp yarn which is'either laid-in in the stitches of the knitting chain or knitted in overlapping stitches. In both cases the modifying warp yarn acts opposite to the knitting chain, so that the legs of the pile projections are in each case clamped between the upper loops of the knitting chain and the modifying warp ends, causing the legs of the pile projections to be erected vertical in the fabric.

Further purposes appear in the specification and in the claims.

In the drawings I have chosen to illustrate one only of the numerous embodiments in which the invention may appear, selecting the forms shown from the standpoints of convenience in illustration, satisfactory operation and,

clear demonstration of the principles involved.

FIGURES l to 8, inclusive, are diagrammatic stepwise vertical sections showing the positions of the operating parts of the knitting machine in producing the fabric of the present invention, particularly directed to FIGURE 9, but serving as a basis for understanding the operations for producing all of the fabrics.

FIGURES 1a to 8a are enlarged and expanded diagrammatic plan views of the knitting according to FIG- URES 1 to 8, to produce the fabric shown in FIGURE 9.

FIGURES 4b and 7b are enlarged expanded diagrammatic plan views of knitting steps which correspond to FIGURES 4a to 7a respectively, but which illustrate thechanges made in the method of FIGURES 1 to 8 and 1a to 8a in order to produce the fabric of FIGURE 14.

FIGURES 4c and 7c are enlarged expanded diagram matic plan views corresponding to FIGURES 4a and 7a;

but showing the modifications in the knitting steps of FIGURES l to 8 and in to 8a which are employed in" producing the fabric of FIGURE 15.

FIGURE id is a view corresponding to FIGURE la,

but showing formation of cut rather than uncut pile.

FIGURE 9 is a fragmentary expanded face of a fabric produced according to FIGURES 1 to 8 and la to 8a.

FIGURE '10 is an enlarged fragmentary section of- FIGURE 9 on the line l0l0.

FIGURE 11 is an enlarged fragmentary plan view showing the face of a fabric according to the invention which knits in or forms coinciding knitting chain stitches for the modifying Warp ends rather than laying them in. The structure of FIGURE 11 applies to all of the other forms, and is illustrated particularly in reference to the pile loop formation of FIGURE 9.

FIGURE 12 is an expanded plan view illustratinga cut pile fabric according to the invention. While the arrangement of the yarn corresponds to FIGURE 9,

Patented Apr. 17, 1962 also in an adjoining stitch of the next, chain.

FIGURE is an enlarged expanded plan view of a modified fabric according to the invention, produced in accordance with FIGURES 4b and7b, and omitting the backing wefts.

FIGURE 16 is an enlarged expanded plan view of a modified fabric according to the invention which is sirnilar to that of FIGURE 15 except that the legs of the pile projections are bound in corresponding stitches of adjoining chains. The backing wefts are omitted.

FIGURE 17 is an enlarged a modified fabric according to the invention which is similar to FIGURE 15 but has the modifying warp ends shogged across and engaged in corresponding stitches of adjoining chains. This omits backing yarn.

FIGURE 18 is a photographic face view of the fabric of FIGURE 9.

FIGURE 19 is a photographic face view of the fabric of FIGURE 15.

Describing in illustration but not in limitation and referring to the drawings:

The fabric and process of the present invention may be produced or carried out on a warp knitting machine of the Raschel type, of the character shown for example in my US. Patent No. 2,891,396, granted June 23, 1959, for Method of Producing a Fabric by Warp Knitting. It will be evident that from the standpoint of the present invention any suitable warp knitting machine of the general Raschel type is applicable, and can be used without any change in the machine except of course to provide suitable loop forming mechanism.

In warp knitted pile fabrics in the prior art it has been the practice insorne cases to bind the legs of the pile projections into stitches of adjoining lines of warp chain stitches in the same course. In other prior art fabrics the legs have been bound in stitches of the same line of chain, or under stretches of binding weft, or in some cases under stretches of adjacent lines of chain warps and adjacent courses.

It will of course be evident that when a leg of a loop is bound into a knitting stitch, it is normally turned into a weftwise direction, and as the leg of the loop is bent upward to for-m the loop this bend from the weftwise direction to the vertical tends to turn the loop, causing many types of yarns to form rows of loops in the same course all of which are oriented in a similar Way and which vary only in alternate adjoining courses. Other types of binding of the loop with the leg resting flat on the fabric have a similar effect on the face of the fabric.

In some cases in Warp knitted pile fabrics, this has been overcome by knitting the pile yarn into the needle stitch, and since the legs of the pile projection are part of the stitch, the appearance of the face'of the fabric is improved. This procedure is impossible, however, with very heavy pile yarns of the type commonly used in carpets, as the knitting needle would have to be so large that it could not be used with an ordinary carpet pitch or gage. Furthermore this procedure is very wasteful of pile yarn.

In the present invention the legs of the pile projections, which may be loops or tufts, are held between two opposed warpwise stretches of yarn, and this forces the legs of the loops into a vertical position or a position close to the vertical. As a result a stiffer pile proexpanded .plan view of jection is formed, and yet, because of the inherent inflexibility of the warpwise stretches, the pile is more resilient, and has more resistance to crushing. Accordingly, the fabric is livelier and less likely to pack down.

In accordance witht the invention it is possible to control the orientation of the pile projection by relatively adjusting the tension of one or both of the controlling warps without any other modifying means. One of the controlling warps is the warp which forms the chain of knitting stitches, and the other of the controlling warps is a modifying warp which is'interlocked with the chain warp, either by co-knitting (forming co-extensive stitches in the same needles) or by laying-in.

Below the bindingpoint the pile yarn may be laid-in into as many warpwise or weftwise stitches as desired for the purpose of increasing the tuft bind, or to get distribution of the yarn ends in color patterns so that individual areas at the face of the pile will appear to be a particular color, as well known in the art. As this action takes place below the binding point of the legs of the'pile projections it has no eifect on the orientation of the pile projections. I

To get the best advantage from the present invention, it is not necessary to bury any pile yarn below the binding of the legs of the pile projection.

In the simplest form of the inven ion each chain warp yarn will be forming warpwise lines of alternate right and lefthand chain stitches which are engaged around bundles of weftwise stretches of backing yarn.

In front of the backing yarn guide bar there will be a pile yarn guide bar and immediately ahead of that there will be a modifying warp yarn guide bar which may or may not form knitting stitches, and then a knitting chain guide bar which will form knitting stitches.

In order to hold the fabric together it is only necessary that the knitting warp yarn form knitting stitches,

but it will be evident that the modifying-warp yarn may be similar to the knitting yarn, but it will in every case run in an opposite direction in each stitch to the direction of the warp knitting guide bar.

In each case when the warp knitting yarn end forms a righthand stitch around the needle hook, the modifyinging yarn end at the same wale will form either a lefthand knitting stitch around the same hook or will be laid-in to the knitting yarn stitch in the opposite direction from the knitting stitch.

The pile yarn will form pile projections on hooks or so-called plush points set to the same gage as the needles, and the new or forward legs of the pile projections, extending back through the knitting yarn and modifying warp yarn, will be locked between the knitting yarn and the modifying warp yarn as the stitch is made and locked.

It will be evident of course that the invention can be embodied in various different forms as later explained.

In one preferable form of the invention, the fabric is particularly well adapted to produce pile carpet with high and low loops of face yarn forming a surface pattern. This technique is responsible for the sharp definition of high and low pattern pile projections which is obtained, as contrasted with the prior art when there is often gradual demarcation between high and low pile.

In this embodiment of the invention the forward leg of each loop as formed is bound onlyunder the stretch of the modifying warp yarn which passes around the base of the pile projection and then into the knitting stitch. At this point in the knitting process the size of the pile loop can be controlled by tension on the pile yarn because the pile loop is very loosely bound. The forward leg of this loop passes across above the top binding stretch of the knitting warp-yarn, and as the next loop is formed and bound in turn by the second warp end, the stitch will not only bind the second warp end in this following stitch but will also bind in what was formerly the leading leg of the previous loop.

t-ional binding points established for the pile projection, which increase the tuft bind.

In FIGURE the grip of the modifying warp end 36 on the leg 58 of the pile projection 47 is clearly shown at 61.

It will be evident that the invention is applicable to cut pile fabrics as well as loop pile fabrics and in FIGURE 12 I show out pile projections 47 produced by the technique of the present invention through the use of a cutting plush point 27' as described in detail in my Patent No. 2,291,- 396 above referred to, and shown in FIGURE Id.

In the forms of the invention thus far described, the modifying yarn end has been laid-in, but the modifying yarn end can if desired actually be knitted with a knitting yarn end in the same needle. FIGURE 11 illustrates an arrangement of this kind, in which the knitting yarn end sonar 34 forms a stitch 62 and provides .a top stretch of this stitch 63 while the modifying yarn end co -knitted forms a stitch '64 which has a top stretch 65. The leg of the loop 47 is here bound at each end at 56 between the top stretches 63 and 65 and the action already described, in erecting the pile projection and also adding to the tuft bind, is obtained. The stitches of course unite together the bundles of backing yarn 41 as previously described.

It will be evident that the co-knitting of the modifying yarn as shown in FIGURE 11 can be employed in any of the embodiments of the invention as desired.

The co-knitting of both the knitting yarn and the modifying warp yarn is advantageous in level pile fabric for hard service where a very strong tuft bind is required. For most purposes, however, the tuft bind of FIGURE 9 or FIGURE 15 is adequate, and when the pile yarn shogs from one chain to another as in FIGURE 16, greater tuft bind is also gained by the extra lay-in of the leg of the pileprojection between the two chains.

In some cases it is preferable to modify the form of FIGURES 1 to 8, 1a to 8a, 9 and 10 by binding the legs of the pile projections in adjoining stitches of the same chain and also in adjoining stitches of adjoining chains, while obtaining the same orienting effect by the modifying warp end. as already described. Thus in FIGURE 13 the pile loop legs 57 and 58 each have stretches 6'7 and 63 which are shogged across to the next knitting chain and bound-in in the corresponding stitches of the next chain, so that the particular pile warp end, instead of remaining always in the same wale, forms pile alternately in adjoining wales.

In some cases it is preferable to bind the legs of the pile projection 47 in the same stitch. This is shown in FIGURE 14, where the legs 57 and 58 of the pile projections 47 are bound in the same knitting stitch, and alsoconnected by stretches 67' and 68 which are shogged across to the next knitting chain and are bound in adjoining stitches in the next knitting chain. In this case each pile projection is fully formed and locked with both legs in the same stitch instead. of having its legs split and locked in successive courses.

In FIGURE 14 the effect of the modifying warp end in erecting the loop and meeting the tuft bind is the same as that described in the previous form.

The technique of producing the fabric of FIGURE 14 is illustrated by FIGURES 4b and 7b.

In FIGURE 4b, corresponding to FIGURE 40!, the modifying yarn ends 36 are shogged to form loops 70 over the new legs of the pile projections as previously described, and it will be evident that both legs of the pile loop 47 are engaged in loop 51 of knitting yarn.

In FIGURE 7b, it will be evident that as shown previously in FIGURE 7a, the pile loop 47 is engaged in the stitch and in this case the nearly completed stitch has secured both ends of the pile loop. The stretch of modifying warp end is shown at 71.

FIGURE 15 shows a further embodiment of the invention, which is particularly adapted for forming high and low pile by control of the feed of the pile yarn so as to produces very high and very low loops in succeeding courses of the same pile yarn ends.

As each succeeding warp stitch is made by the needles, loops of yarn form around the plush points, and the leading or forward legs of each pile projection is crossed and held by the modifying Warp yarn at 72 as shown in FIGURE 15. The modifying warp yarn as in the previous forms always runs opposite to the looping motion. of the knitting yarn stitch. As the knitting stitch is formed, the knitting stitch does not catch the forward leg of the pile loop at the time of loop formation, but instead merely locks the modifying warp ends which are holding the forward legs of the pile loops 47 at 72. The knitting yarn stitch, however, does knit in the last leg of the loop which was the forward leg of the previous loop as shown at 73 in FIGURE 15, because the pile loop in forming crosses in front of the knitting yarn.

Thus it will be evident that the modifying warp yarn passes around the forward leg of the pile projection and then 'under the top stretch of the warp knitting yarn in the same course, the forward leg of the pile projection avoiding the path of the warp knitting stitch of the same course, and the forward leg of the previous pile projection is lapped under the top stretch of the warp knitting yarn of the next stitch and course, it not being lapped under the knitting yarn of the previous course.

Thus it is that each pile loop as it is formed is bound only by the relatively loose stretch 60 of the modifying warp yarn end, and the pile loop 47 in consequence is subject to being pulled back until it is non-existent or just a flat end in the surface, or it may be allowed to remain at its full height, or it may be pulled down to any intermediate height, as suggested by the dotted line 74 in FIGURE 15. This is accomplished by a pattern control of the character of the MacCaifray patents and Masland patents aforesaid, which control each individual pile yarn end as it is fed during each stitch. The pile yarn loop. remains at this height locked only by the modifying warp end until the next succeeding, knitting stitch is formed, at which time the pile loop will be locked completely by the knitting stitch and will almost appear as though it had been formed by the original double locking method of FIGURE 9.

FIGURE 40 at in the cycle illustrates the formation of the loop 47 which is locked in the stitch at one end and is locked at the other end only at 72 by the modifying warp end 36, and FIGURE 7c at 300 in the cycle shows that this condition remains even when the knitting yarn stitch is nearly completed at 51. FIG- URES 4c and 7c otherwise correspond to FIGURES 4a and 7a.

It will be evident that if desired'the control of the modulation of the tension on the modifying warp ends as well. as the modulation of. the tension on the pile warp ends may be employed in FIGURE 15, in which case there will be differences in orientation as well as differences in height of the different pile projections.

FIGURE 16 shows' a fabric which in other respects is similar to that of FIGURE 15 with the same locking of the pile projection as that of FIGURE 15, namely, by the modifying warp stretch 60 as well as by the succeeding knitting stitc In this case, however, there are stretches 67 of pile yarn ends which extend across and provide locking of the legs of the pile projection also in the corresponding stitch of the next knitting chain 53. In.

this case the pile projections of any particular yarn end will not come up in the same knitting chain on two succeeding courses.

FIGURE 17 illustrates another embodiment of the invention which in this case is similar to that of FIGURE 15, except that between the stretches 60 of the modifying yarn ends they shog across weftwise at 75 to the next knitting chain and are engaged in the corresponding stitches of the same course. This provides a somewhat different form of double bind, but the erection of the pile .It will be evident however, that when level pile is formed, it is more advantageous to form the loop of pile yarn in such a way that the leading leg of the loop will be knitted into the existing and forming knitting stitch.

First considering the form of the invention as embodied in FIGURES l to 8, la to 8a, 9 and 10, the warp knitting machine is suitably a double needle bar Raschel type, one needle bar mounting supports 20 for a series of latch needles 21, as well known, which extend vertically and are guided by a trick plate 22, which is tapered and extends generally vertically, the fabric being taken off at one side and the needles being guided at the other side.

The latch needles, as well known, have hooked ends 23 at the top directed away from the trick plate, and latches 24 pivoted at 25, and in one position closing against the hook ends.

The other needle bar in the device of the invention is equipped with a plush point mounting 26 which carries generally vertically extending plush points 27. The plush points can be cutting or non-cutting as desired, and as later explained in more detail, but FIGURES l to 8 show non-cutting plush points which at the upper ends toward the trick plate have recesses 28.

A sinker comb 36, as well known, is mounted on sinker supports 31 and moves across the top of the trick plate. A latch wire 32 extends across the back of the machine.

A swing bar across the machine supports a series of separately shoggable guide bars of well known character, comprising a knitting yarn guide bar 33 having eyes which guide knitting yarn 34, a modifying yarn guide bar 35 having eyes which guide modifying yarn ends 36, a pile yarn guide bar 37 having eyes which guide pile yarn ends 38, and a backing yarn guide bar 40 having eyes which guide backing yarn ends 41. The various ends are suitably placed at each needle position in the preferred embodiment.

Considering now particularly FIGURES 1 to 8 and In to 8:1, in FIGURES l and la which correspond to zero or 360 in the cycle, the first step is being taken after completion of the last stitch, the needles 21 and the plush points 27 are down or retracted, the sinker comb 30 is advanced or forward, and the swing bar with the various guide bars is in mid-position and moving back. At this position the backing yarn guide bar shogs to lay-in stretches 42 of backing yarn.

FIGURES 2 and 2a correspond to 30 of advance in the cycle. The position of the needles and of the sinkers is the same as in FIGURE 1. The guide bars are all the way back, out of line with the needles and the plush points, and the plush points have just completed their forward or upward motion. If the plush points are cutting as later explained' (FIGURE 1d) they will at this point out the previous loops.

Backing yarn guide bar 40 continues to shog in the same direction forming backing yarn stretches 43.

FIGURES 3 and 3a correspond to the position at 90 in the cycle. The swing bar and the guide bars with it move to the front past the raised plush points and pile yarn guide bar 37 now shogs so that in the next succeedings step pile loops will be formed around the plush points as .well known in the art. The formation of such loops is shown at 44 in FIGURE 3a.

At 150 in the cycle, as shown in FIGURES 4 and 4a, the swing bar has moved back, carrying with it the guide bars, while the position of all of the other elements remains the same. Modifying yarn guide bar 35 now shogs to form stretches 45 over the new legs of loops 46 of pile yarn 38.

The position at FIGURES and 50:, corresponding to 210 in the cycle, corresponds to the completion of all shogging except for the knitting yarn. The pile yarn and knitting yarn guide bars have moved forward past the plush points. Depending on the shogging positions, the pile yarn has formed loops 47 around the plush points. The needles 21 have advanced or raised and the latches 24 of the needles have been opened by the previous knitting stitch as shown at 48 and as well known.

The position of FIGURES 6 and 6a corresponds to 270 in the cycle. All guide bars have moved back of the plush points and the needles, and the new stitch is ready to be formed when it enters the hook of the needles in the next step. The pile yarn ends are now arranged in more completely formed loops 47 around the plush points and the backing yarn is now laid-in in stretches 50 in the stitches, while the knitting yarn guide bar 33 is now shogging to place the knitting yarn in the hooks of the needles above the latches. This forms loops 51 of knitting yarn.

In FIGURES 7 and 7a at 300 in the cycle, the guide bars are moving to the front and are midway in their swing. The sinker comb 30, which has been in position across the fell and across the end of the trick plate and among the plush points, is now retracted to clear the ends of the needles, and the needles are beginning to retract and the latch is closed by the previous stitch, and the plush points are retracting. The effect therefore is to bind the stretches 52 of modifying warp yarn 36 and bind the forward legs of thepile projections 47, with the stretches of knitting yarn and of modifying warp yarn on opposite sides of the legs of the pile projections.

FIGURES 8 and 8a, corresponding to 330 in the cycle, show the guide bars moving to the front and midway in their swing. The sinker comb 39 is fully retracted and is now about to advance again to the position of FIGURE 1. The needles have fully retracted.

By reference to FIGURES 9 and 10, it will be evident that the completed fabric comprises a series of warpwise chains of successive righthand and lefthand stitches 53, each of which has bottom stretches 54 and a top stretch 55. Engaged in stitches between the top and bottom stretches are bundles 56 of weftwise stretches of backing yarn 41. The pileprojections 47, have legs 57 and 58 which are bound beneath the top stretches of successive knitting stitches of the same knitting chain. 0n the opposite side of each pile projection from the top stretch of each stitch is a stretch 60 of modifying warp yarn- 36 which is running warpwise engaged beneath the top stretch of each stitch and extending sinuously. The stretches 60 of the modifying warp yarn '36 are always opposite to the direction of formation of the stitch in any course.

Thus each modifying warp end 36, in this form remains in one line of chain stitches. The tension of the modifying warp end with respect to the tension of the chain is important and will suitably be controlled and in some cases modulated in the present invention. The tension of the knitting chain should always be higher than that of the modifying warp end.

A typical knitting yarn tension is likely to be of the order of two pounds per end and as compared with this the modifying yarn tension where the modifying yarn is laid-in is likely to be of the order of from three to six ounces, but where the modifying yarn is co-knitted it will be of the order of one to almost two pounds.

It will be evident that the tension of the modifying warp end can be controlled from stitch to stitch using a pattern control mechanism as shown in the following U.S. patents: Rex S. MacCafiray, Jr. U.S. Patents Nos. 2,784,689 and Frank W. E. Hoeselbarth Patent No. 2,842,259 C. H. Masland 2nd, U.S. Patents Nos. 2,866,424 and It will be noted that as each stitch of knitting warp yarn is formed, it also binds in a stretch of modifying warp yarn and binds the forward leg of the pile projection. As the stitch is locked the pile loop legs 57 and 58 are locked. These locking points are formed by the pressure of the modifying warp end stretch 60. The effect is to erect the pile projections (the plan views show it lying down according to a convention well known in the art to permit seeing it as a pile loop, but actually the pile projection extends upwardly). In the second place there are addi- 9 projections is similar to that in the other forms of the invention. 7 t

In view of my invention and disclosure, variations and modifications to meet individual whim or particular need will doubtless become evident to others skilled in the aft, to obtain all or part of the benefits of my invention without copying the process and fabric shown, and I, there"- fore, claim all such insofar as they fall within the reasonable spirit and scope of my claims.

Having thus described my invention what I claim as new and desire to secure by Letters Patent is:

l. The method of warp knitting a pile fabric using a Raschel type knitting machine having a gang of united knitting needles, a gang of united pile loop forming plush points, a trick plate between the needles and plush points and adjacent to the needles, at least four yarn guide bars which shog separately but move in unison over the needles and plush points, with a warp of yarn supplied to each yarn guide bar, the yarn guide bars and the warps in order from the plush point side to the needle side being (1) a knitting yarn guide bar and Warp; (2) a modifying yarn guide bar and warp; (3) a face yarn guide bar and warp; (4) and a backing yarn guide bar and warp, which method comprising moving the backing yarn guide bar and warp to form a backing yarn inlay, advancing the plush points, moving the face yarn guide bar and warp to form a face yarn loop having legs around each plush point, moving the modifying yarn guide bar and Warp to form a stretch of each modifying warp yarn around and over the new legs of each of the newly formed face loops, raising the needles to allow the loops of the knitting yarn from the previous stitch to move down the shanks of the needles and leave the hooks of the needles open, moving the knitting yarn guide bar and warp in a direction of movement opposite to the previous movement of the modifying warp yarn guide bar in the same stitch to place a top stretch of each knitting yarn around the new stretch of modifying warp yarn and also around the inlay of backing yarn, and then moving the knitting yarn guide bar and the warp of knitting yarn to place each said stretch of knitting yarn also into the hook of each needle, retracting the needles to cast oflf the previous stitch loops and complete the present stitch, the legs of the loops being thus held between the said top stretch of knitting yarn on one side of the said legs and the said stretch of modifying warp yarn on the other side of the said leg of the loop.

2. The method of claim 1, which comprises forming parallel lines of knitted stitches all of one character, righthand or lefthand, forming pile projections around the plush points, moving modifying warp yarn around and over the legs of each of the pile projections, forming an inlay of backing yarn, and binding into the knitted stitches the legs of the pile projections, the ends of the said stretch of modifying warp yarn and the backing am. y 3. The method of claim 1, which comprises binding 10 the opposite legs of the pile projections in successive stitches of the same line of knitted stitches.

4. The method of claim 1, which comprises binding the opposite legs of the pile projections in successive stitches of the same knitted chain and also in adjoining stitches of the next knitted chain.

5. The method of claim 1, which comprises binding both legs of the pile projections in the same stitch of the knitted chain.

6. The method of claim 1, which comprises binding both legs of the pile projections in the same stitch of the knitted chain and also in an adjoining stitch of the next knitted chain.

7. The method of claim 1, which comprises moving the modifying warp yarn around and over the legs of the pile projection of pile yarn around the plush point.

8. The method of claim 1, which comprises moving the modifying warp yarn around and over the legs of the pile projection of the pile yarn around the plush point and anchoring the opposite leg of the pile projection in adjoining stitches of the same knitted chain.

9. The method of claim 1, which comprises moving the modifying warp yarn around and over the leg of the pile projection of pile yarn around the plush point and anchoring the opposite legs of the pile projection in adjoining knitted stitches of two adjoining knitted chains.

10. The method of claim 1, which comprises laying-in the modifying warp yarn in the stitches of adjoining knitted chains.

11. The method of claim 1, which comprises forming the suc cesive knitted stitches and running the modifying warp yarn simultaneously warpwise through the stitches.

12. The method of claim 1, which comprises moving the modifying warp yarn around and over the legs of the pile projections on the plush points, and varying the tension of the pile Warp yarn at different stitches to cause formation of pile projections over different height by pulling back under the bind of the modifying warp yarn before the forward leg of the pile projection is locked in the next stitch.

13. The method of claim 12, which comprises also varying the tension of the modifying warp yarn selectively to vary the orientation of the pile.

14. The method of claim 1, which comprises varying the tension on the modifying warp yarn at selective stitches and therefore varying the orientation of the pile.

15. The method of claim 1, which comprises concurrently varying the tension on the pile warp yarn and varying the tension on the modifying warp yarn selectively to vary both the height and the orientation of the pile.

References Cited in the file of this patent UNITED STATES PATENTS 2,891,396 MacCaifray June 23, 1959 2,899,813 Herrnstadt et a1 Aug. 18, 1959 2,931,197 Newman Apr. 5, 1960 

